N,6-bis(aryl or heteroaryl)-1,3,5-triazine-2,4-diamine compounds as idh2 mutants inhibitors for the treatment of cancer

ABSTRACT

Provided are compounds of formula (I), Wherein: ring A and ring B are each independently an optionally substituted 5-6 membered monocyclic aryl or heteroaryl. The compounds are inhibitors of isocitrate dehydrogenase 2 (IDH2) mutants useful for treating cancer.

CLAIM OF PRIORITY

This application claims priority from U.S. Application Ser. No.61/845,352 filed Jul. 11, 2013, which is incorporated herein byreference in its entirety.

BACKGROUND OF INVENTION

Isocitrate dehydrogenases (IDHs) catalyze the oxidative decarboxylationof isocitrate to 2-oxoglutarate (i.e., α-ketoglutarate). These enzymesbelong to two distinct subclasses, one of which utilizes NAD(+) as theelectron acceptor and the other NADP(+). Five isocitrate dehydrogenaseshave been reported: three NAD(+)-dependent isocitrate dehydrogenases,which localize to the mitochondrial matrix, and two NADP(+)-dependentisocitrate dehydrogenases, one of which is mitochondrial and the otherpredominantly cytosolic. Each NADP(+)-dependent isozyme is a homodimer.

IDH2 (isocitrate dehydrogenase 2 (NADP+), mitochondrial) is also knownas IDH; IDP; IDHM; IDPM; ICD-M; or mNADP-IDH. The protein encoded bythis gene is the NADP(+)-dependent isocitrate dehydrogenase found in themitochondria. It plays a role in intermediary metabolism and energyproduction. This protein may tightly associate or interact with thepyruvate dehydrogenase complex. Human IDH2 gene encodes a protein of 452amino acids. The nucleotide and amino acid sequences for IDH2 can befound as GenBank entries NM_002168.2 and NP_002159.2 respectively. Thenucleotide and amino acid sequence for human IDH2 are also described in,e.g., Huh et al., Submitted (November-1992) to the EMBL/GenBank/DDBJdatabases; and The MGC Project Team, Genome Res. 14:2121-2127(2004).

Non-mutant, e.g., wild type, IDH2 catalyzes the oxidativedecarboxylation of isocitrate to α-ketoglutarate (α-KG) thereby reducingNAD⁺ (NADP⁺) to NADH (NADPH), e.g., in the forward reaction:

Isocitrate+NAD⁺(NADP⁺)→α-KG+CO₂+NADH(NADPH)+H⁺.

It has been discovered that mutations of IDH2 present in certain cancercells result in a new ability of the enzyme to catalyze theNAPH-dependent reduction of α-ketoglutarate to R(−)-2-hydroxyglutarate(2HG). 2HG is not formed by wild-type IDH2. The production of 2HG isbelieved to contribute to the formation and progression of cancer (Dang,L et al, Nature 2009, 462:739-44).

The inhibition of mutant IDH2 and its neoactivity is therefore apotential therapeutic treatment for cancer. Accordingly, there is anongoing need for inhibitors of IDH2 mutants having alpha hydroxylneoactivity.

SUMMARY OF INVENTION

Described herein are compounds of Structural Formula I, or apharmaceutically acceptable salt or hydrate thereof:

wherein:

-   -   ring A is an optionally substituted 5-6 member monocyclic aryl        or monocyclic heteroaryl; and    -   ring B is an optionally substituted 5-6 member monocyclic aryl        or monocyclic heteroaryl; wherein:    -   a. ring A and ring B are not both an optionally substituted 6        member monocyclic aryl;    -   b. when ring A is unsubstituted pyridyl, then ring B is not        phenyl optionally substituted with one to three groups        independently selected from methyl, ethyl, t-butyl, methoxy,        CH(OH)CH₃, Cl, Br, SH, and CF₃;    -   c. when ring A is a 5-membered heteroaryl, then ring B is not        phenyl optionally substituted with one to two groups        independently selected from F, Cl, SO₂CH₃, C(O)OCH₃, methyl,        ethyl, t-butyl, methoxy, ethoxy, O-phenyl, CF₃, OH, and NO₂;    -   d. when ring A is a 2,4-di-substituted 5-thiazolyl, then ring B        is not substituted phenyl;    -   e. the compound is not:        -   (1)            N²-2-pyridinyl-6-(3-pyridinyl)-1,3,5-triazine-2,4-diamine;        -   (2)            6-(6-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;        -   (3)            6-(2-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;        -   (4)            N²-(3-chlorophenyl)-6-(2-chloro-4-pyridinyl)-1,3,5-triazine-2,4-diamine;        -   (5)            3-[[4-[4-amino-6-[(3-chlorophenyl)amino]-1,3,5-triazin-2-yl]-2-pyridinyl]amino]-1-propanol;        -   (6)            N-[3-[[4-amino-6-(2-methyl-4-pyrimidinyl)-1,3,5-triazin-2-yl]amino]-4-methylphenyl]-N′-[4-chloro-3-(trifluoromethyl)phenyl]-urea;        -   (7)            N⁴,N^(4′)-diphenyl-[2,2′-bi-1,3,5-triazine]-4,4′,6,6′-tetramine;        -   (8)            6,6′-(2,6-pyridinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine;            or        -   (9)            6,6′-(2,3-pyrazinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine.

The compound of Formula I or II or as described in any one of theembodiments herein inhibits mutant IDH2, particularly mutant IDH2 havingalpha hydroxyl neoactivity. Also described herein are pharmaceuticalcompositions comprising a compound of Formula I and methods of usingsuch compositions to treat cancers characterized by the presence of amutant IDH2.

DETAILED DESCRIPTION

The details of construction and the arrangement of components set forthin the following description or illustrated in the drawings are notmeant to be limiting. Other embodiments and different ways to practicethe invention are expressly included. Also, the phraseology andterminology used herein is for the purpose of description and should notbe regarded as limiting. The use of “including,” “comprising,” or“having,” “containing”, “involving”, and variations thereof herein, ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items.

DEFINITIONS

The term “halo” or “halogen” refers to any radical of fluorine,chlorine, bromine or iodine.

The term “alkyl” refers to a fully saturated or unsaturated hydrocarbonchain that may be a straight chain or branched chain, containing theindicated number of carbon atoms. For example, C₁-C₁₂ alkyl indicatesthat the group may have from 1 to 12 (inclusive) carbon atoms in it. Theterm “haloalkyl” refers to an alkyl in which one or more hydrogen atomsare replaced by halo, and includes alkyl moieties in which all hydrogenshave been replaced by halo (e.g., perfluoroalkyl). The terms “arylalkyl”or “aralkyl” refer to an alkyl moiety in which an alkyl hydrogen atom isreplaced by an aryl group. Aralkyl includes groups in which more thanone hydrogen atom has been replaced by an aryl group. Examples of“arylalkyl” or “aralkyl” include benzyl, 2-phenylethyl, 3-phenylpropyl,9-fluorenyl, benzhydryl, and trityl groups. The term “alkyl” includes“alkenyl” and “alkynyl”.

The term “alkylene” refers to a divalent alkyl, e.g., —CH₂—, —CH₂CH₂—,—CH₂CH₂CH₂— and —CH₂CH(CH₃)CH₂—.

The term “alkenyl” refers to a straight or branched hydrocarbon chaincontaining 2-12 carbon atoms and having one or more double bonds.Examples of alkenyl groups include, but are not limited to, allyl,propenyl, 2-butenyl, 3-hexenyl and 3-octenyl groups. One of the doublebond carbons may optionally be the point of attachment of the alkenylsubstituent.

The term “alkynyl” refers to a straight or branched hydrocarbon chaincontaining 2-12 carbon atoms and characterized in having one or moretriple bonds. Examples of alkynyl groups include, but are not limitedto, ethynyl, propargyl, and 3-hexynyl. One of the triple bond carbonsmay optionally be the point of attachment of the alkynyl substituent.

The term “alkoxy” refers to an —O-alkyl radical. The term “haloalkoxy”refers to an alkoxy in which one or more hydrogen atoms are replaced byhalo, and includes alkoxy moieties in which all hydrogens have beenreplaced by halo (e.g., perfluoroalkoxy).

Unless otherwise specified, the term “aryl” refers to a fully aromaticmonocyclic, bicyclic, or tricyclic hydrocarbon ring system. Examples ofaryl moieties are phenyl, naphthyl, and anthracenyl. Unless otherwisespecified, any ring atom in an aryl can be substituted by one or moresubstituents. The term “monocyclic aryl” means a monocyclic fullyromatic hydrocarbon ring system, optionally substituted by one or moresubstituents which can not form a fused bicyclic or tricyclic ring.

The term “carbocyclyl” refers to a non-aromatic, monocyclic, bicyclic,or tricyclic hydrocarbon ring system. Carbocyclyl groups include fullysaturated ring systems (e.g., cycloalkyls), and partially saturated ringsystems.

The term “cycloalkyl” as employed herein includes saturated cyclic,bicyclic, tricyclic, or polycyclic hydrocarbon groups having 3 to 12carbons. Any ring atom can be substituted (e.g., by one or moresubstituents). Examples of cycloalkyl moieties include, but are notlimited to, cyclopropyl, cyclohexyl, methylcyclohexyl, adamantyl, andnorbornyl.

Unless otherwise specified, the term “heteroaryl” refers to a fullyaromatic 5-8 membered monocyclic, 8-12 membered bicyclic, or 11-14membered tricyclic ring system having 1-3 heteroatoms if monocyclic, 1-6heteroatoms if bicyclic, or 1-9 heteroatoms if tricyclic, saidheteroatoms selected from O, N, or S (or the oxidized forms such asN⁺—O⁻, S(O) and S(O)₂). The term “monocyclic heteroaryl” means amonocyclic fully romatic ring system having 1-3 heteroatoms, optionallysubstituted by one or more substituents which can not form a fusedbicyclic or tricyclic ring.

The term “heterocyclyl” refers to a nonaromatic, 3-10 memberedmonocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic ringsystem having 1-3 heteroatoms if monocyclic, 1-6 heteroatoms ifbicyclic, or 1-9 heteroatoms if tricyclic, said heteroatoms selectedfrom O, N, or S (or the oxidized forms such as N⁺—O⁻, S(O) and S(O)₂).The heteroatom may optionally be the point of attachment of theheterocyclyl substituent. Examples of heterocyclyl include, but are notlimited to, tetrahydrofuranyl, tetrahydropyranyl, piperidinyl,morpholino, pyrrolinyl, pyrimidinyl, and pyrrolidinyl. Heterocyclylgroups include fully saturated ring systems, and partially saturatedring systems.

Bicyclic and tricyclic ring systems containing one or more heteroatomsand both aromatic and non-aromatic rings are considered to beheterocyclyl or heteroaryl groups. Bicyclic or tricyclic ring systemswhere an aryl or a heteroaryl is fused to a carbocyclyl or heterocyclyland the point of attachment from the ring system to the rest of themolecule is through an aromatic ring are considered to be aryl orheteroaryl groups, respectively. Bicyclic or tricyclic ring systemswhere an aryl or a heteroaryl is fused to a carbocyclyl or heterocyclyland the point of attachment from the ring system to the rest of themolecule is through the non-aromatic ring are considered to becarbocyclyl (e.g., cycloalkyl) or heterocyclyl groups, respectively.

Aryl, heteroaryl, carbocyclyl (including cycloalkyl), and heterocyclylgroups, either alone or a part of a group (e.g., the aryl portion of anaralkyl group), are optionally substituted at one or more substitutableatoms with, unless specified otherwise, substituents independentlyselected from: halo, —C≡N, C₁-C₄ alkyl, ═O, —OR^(b), —OR^(b′), —SR^(b),—SR^(b′), —(C₁-C₄ alkyl)-N(R^(b))(R^(b)), —(C₁-C₄alkyl)-N(R^(b))(R^(b′)), —N(R^(b))(R^(b)), —N(R^(b))(R^(b′)), —O—(C₁-C₄alkyl)-N(R^(b))(R^(b)), —O—(C₁-C₄ alkyl)-N(R^(b))(R^(b′)), —(C₁-C₄alkyl)-O—(C₁-C₄ alkyl)-N(R^(b))(R^(b)), —(C₁-C₄ alkyl)-O—(C₁-C₄alkyl)-N(R^(b))(R^(b′)), —C(O)—N(R^(b))(R^(b)), —(C₁-C₄alkyl)-C(O)—N(R^(b))(R^(b)), —(C₁-C₄ alkyl)-C(O)—N(R^(b))(R^(b′)),—OR^(b′), R^(b′), —C(O)(C₁-C₄ alkyl), —C(O)R^(b′),—C(O)N(R^(b′))(R^(b)), —N(R^(b))C(O)(R^(b)), —N(R^(b))C(O)(R^(b′)),—N(R^(b))SO₂(R^(b)), —SO₂N(R^(b))(R^(b)), —N(R^(b))SO₂(R^(b′)), and—SO₂N(R^(b))(R^(b′)), wherein any alkyl substituent is optionallyfurther substituted with one or more of —OH, —O—(C₁-C₄ alkyl), halo,—NH₂, —NH(C₁-C₄ alkyl), or —N(C₁-C₄ alkyl)₂;

-   -   each R^(b) is independently selected from hydrogen, and —C₁-C₄        alkyl; or    -   two R^(b)s are taken together with the nitrogen atom to which        they are bound to form a 4- to 8-membered heterocyclyl        optionally comprising one additional heteroatom selected from N,        S, and O; and    -   each R^(b′) is independently selected from C₃-C₇ carbocyclyl,        phenyl, heteroaryl, and heterocyclyl, wherein one or more        substitutable positions on said phenyl, cycloalkyl, heteroaryl        or heterocycle substituent is optionally further substituted        with one or more of —(C₁-C₄ alkyl), —(C₁-C₄ fluoroalkyl), —OH,        —O—(C₁-C₄ alkyl), —O—(C₁-C₄ fluoroalkyl), halo, —NH₂, —NH(C₁-C₄        alkyl), or —N(C₁-C₄ alkyl)₂.

Heterocyclyl groups, either alone or as part of a group, are optionallysubstituted on one or more any substitutable nitrogen atom with oxo,—C₁-C₄ alkyl, or fluoro-substituted C₁-C₄ alkyl.

The term “substituted” refers to the replacement of a hydrogen atom byanother group.

As used herein, the term “elevated levels of 2HG” means 10%, 20% 30%,50%, 75%, 100%, 200%, 500% or more 2HG then is present in a subject thatdoes not carry a mutant IDH2 allele. The term “elevated levels of 2HG”may refer to the amount of 2HG within a cell, within a tumor, within anorgan comprising a tumor, or within a bodily fluid.

The term “bodily fluid” includes one or more of amniotic fluidsurrounding a fetus, aqueous humour, blood (e.g., blood plasma), serum,Cerebrospinal fluid, cerumen, chyme, Cowper's fluid, female ejaculate,interstitial fluid, lymph, breast milk, mucus (e.g., nasal drainage orphlegm), pleural fluid, pus, saliva, sebum, semen, serum, sweat, tears,urine, vaginal secretion, or vomit.

As used herein, the terms “inhibit” or “prevent” include both completeand partial inhibition and prevention. An inhibitor may completely orpartially inhibit the intended target.

The term “treat” means decrease, suppress, attenuate, diminish, arrest,or stabilize the development or progression of a disease/disorder (e.g.,a cancer), lessen the severity of the disease/disorder (e.g., a cancer)or improve the symptoms associated with the disease/disorder (e.g., acancer).

As used herein, an amount of a compound effective to treat a disorder,or a “therapeutically effective amount” refers to an amount of thecompound which is effective, upon single or multiple dose administrationto a subject, in treating a cell, or in curing, alleviating, relievingor improving a subject with a disorder beyond that expected in theabsence of such treatment.

As used herein, the term “subject” is intended to include human andnon-human animals. Exemplary human subjects include a human patient(referred to as a patient) having a disorder, e.g., a disorder describedherein or a normal subject. The term “non-human animals” of one aspectof the invention includes all vertebrates, e.g., non-mammals (such aschickens, amphibians, reptiles) and mammals, such as non-human primates,domesticated and/or agriculturally useful animals, e.g., sheep, dog,cat, cow, pig, etc.

Compounds

Provided is a compound of Structural Formula I, or a pharmaceuticallyacceptable salt or hydrate thereof:

wherein:

-   -   ring A is an optionally substituted 5-6 member monocyclic aryl        or monocyclic heteroaryl; and    -   ring B is an optionally substituted 5-6 member monocyclic aryl        or monocyclic heteroaryl; wherein:    -   a. ring A and ring B are not both an optionally substituted 6        member monocyclic aryl;    -   b. when ring A is unsubstituted pyridyl, then ring B is not        phenyl optionally substituted with one to three groups        independently selected from methyl, ethyl, t-butyl, methoxy,        CH(OH)CH₃, Cl, Br, SH, and CF₃;    -   c. when ring A is a 5-membered heteroaryl, then ring B is not        phenyl optionally substituted with one to two groups        independently selected from F, Cl, SO₂CH₃, C(O)OCH₃, methyl,        ethyl, t-butyl, methoxy, ethoxy, O-phenyl, CF₃, OH, and NO₂;    -   d. when ring A is a 2,4-di-substituted 5-thiazolyl, then ring B        is not substituted phenyl;    -   e. the compound is not:        -   (1)            N²-2-pyridinyl-6-(3-pyridinyl)-1,3,5-triazine-2,4-diamine;        -   (2)            6-(6-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;        -   (3)            6-(2-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;        -   (4)            N²-(3-chlorophenyl)-6-(2-chloro-4-pyridinyl)-1,3,5-triazine-2,4-diamine;        -   (5)            3-[[4-[4-amino-6-[(3-chlorophenyl)amino]-1,3,5-triazin-2-yl]-2-pyridinyl]amino]-1-propanol;        -   (6)            N-[3-[[4-amino-6-(2-methyl-4-pyrimidinyl)-1,3,5-triazin-2-yl]amino]-4-methylphenyl]-N′-[4-chloro-3-(trifluoromethyl)phenyl]-urea;        -   (7)            N⁴,N^(4′)-diphenyl-[2,2′-bi-1,3,5-triazine]-4,4′,6,6′-tetramine;        -   (8)            6,6′-(2,6-pyridinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine;            or        -   (9)            6,6′-(2,3-pyrazinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine.

In some embodiments, ring A is an optionally substituted 6-memberedmonocyclic aryl. In some embodiments, ring A is an optionallysubstituted 5-6 membered heteroaryl. In some embodiments, ring A is anoptionally substituted 6 membered heteroaryl.

In some embodiments, ring A is selected from phenyl, pyrazolyl,oxazolyl, isoxazolyl, pyridinyl, pyrimidinyl, pyrazinyl, and thiazolyl,wherein ring A is optionally substituted with up to two substituentsindependently selected from halo, —C₁-C₄ alkyl, —C₁-C₄ haloalkyl, —C₁-C₄hydroxyalkyl, —NH—S(O)₂—(C₁-C₄ alkyl), —S(O)₂NH(C₁-C₄ alkyl), —CN,—S(O)₂—(C₁-C₄ alkyl), C₁-C₄ alkoxy, —NH(C₁-C₄ alkyl), —OH, —OCF₃, —CN,—NH₂, —C(O)NH₂, —C(O)NH(C₁-C₄ alkyl), —C(O)—N(C₁-C₄ alkyl)₂, andcyclopropyl optionally substituted with OH.

In some embodiments, ring A is selected from phenyl, pyrazolyl,oxazolyl, isoxazolyl, pyridinyl, pyrimidinyl, pyrazinyl, and thiazolyl,wherein ring A is optionally substituted with up to two substituentsindependently selected from halo, —C₁-C₄ alkyl, —C₁-C₄ haloalkyl, —C₁-C₄hydroxyalkyl, —NH—S(O)₂—(C₁-C₄ alkyl), —S(O)₂NH(C₁-C₄ alkyl), —CN,—S(O)₂—(C₁-C₄ alkyl), C₁-C₄ alkoxy, —NH(C₁-C₄ alkyl), —OH, —CN, and—NH₂.

In some embodiments, ring B is selected from phenyl, pyrazolyl,oxazolyl, isoxazolyl, thiazolyl, pyridinyl, pyrimidinyl, pyridazinyl,and pyrazinyl, wherein ring B is optionally substituted with up to twosubstituents independently selected from halo, —C₁-C₄ alkyl, —C₂-C₄alkynyl, —C₁-C₄ haloalkyl, —C₁-C₄ hydroxyalkyl, C₃-C₆ cycloalkyl,—(C₀-C₂ alkylene)-O—C₁-C₄ alkyl, —O—(C₁-C₄ alkylene)-C₃-C₆ cycloalkyl,—NH—S(O)₂—(C₁-C₄ alkyl), —S(O)₂NH(C₁-C₄ alkyl), —S(O)₂—NH—(C₃-C₆cycloalkyl), —S(O)₂-(saturated heterocyclyl), —CN, —S(O)₂—(C₁-C₄ alkyl),—NH(C₁-C₄ alkyl), —N(C₁-C₄ alkyl)₂, —OH, C(O)—O—(C₁-C₄ alkyl), saturatedheterocyclyl, and —NH₂.

In another embodiment, the compound is a compound having StructuralFormula II:

or a pharmaceutically acceptable salt thereof, wherein:

ring A′ is selected from phenyl, pyrimidin-2-yl, pyrimidin-4-yl,pyrimidin-5-yl, oxazol-4-yl, isoxazol-3-yl, thiazol-2-yl, pyridin-3-yland pyridin-2-yl, wherein ring A′ is optionally substituted with one ortwo substituents independently selected from 1-propenyl,-cyclopropyl-OH, chloro, fluoro, —CF₃, —CHF₂, —CH₃, —CH₂CH₃, —CF₂CH₃,—S(O)CH₃, —S(O)₂CH₃, —CH₂OH, —CH(OH)CH₃, —CH(OH)CF₃, —OH, —OCH₃, —OCF₃,—OCH₂CH₃, —C(O)—NH₂, —CH₂NH₂, —NH₂, —NH(CH₃), —CN and —N(CH₃)₂; and

ring B′ is selected from phenyl, pyridin-3-yl, pyridin-4-yl,pyridazin-4-yl, isoxazol-4-yl, isoxazol-3-yl, thiazol-5-yl,pyrimidin-5-yl and pyrazol-4-yl, wherein ring B′ is optionallysubstituted with one to two substituents independently selected fromhalo; —CN; —OH; C₁-C₄ alkyl optionally substituted with halo, CN or —OH;—S(O)₂—C₁-C₄ alkyl; —S(O)—C₁-C₄ alkyl; —S(O)₂—NH—C₁-C₄ alkyl;—S(O)₂—NH—CH₂—CF₃; —S(O)₂—N(C₁-C₄ alkyl)₂; —S(O)₂-azetidin-1-yl;—O—C₁-C₄ alkyl; —CH₂—O—CH₃, morpholin-4-yl, cyclopropyl,cyclopropyl-C₁-C₄ alkyl, cyclopropyl-C₁-C₄ alkoxy, cyclopropyl-CN,—S(O)₂—NH-cyclopropyl; —S(O)₂—NH—CH₂-cyclopropyl; —C(O)—C₁-C₄ alkyl,—C(O)—O—CH₃; wherein:

-   -   a. ring A′ and ring B′ are not both an optionally substituted 6        member monocyclic aryl;    -   b. when ring A′ is unsubstituted pyridyl, then ring B′ is not        phenyl optionally substituted with one to three groups        independently selected from methyl, ethyl, t-butyl, methoxy,        CH(OH)CH₃, Cl, Br, SH, and CF₃;    -   c. when ring A′ is a 5-membered heteroaryl, then ring B′ is not        phenyl optionally substituted with one to two groups        independently selected from F, Cl, SO₂CH₃, C(O)OCH₃, methyl,        ethyl, t-butyl, methoxy, ethoxy, O-phenyl, CF₃, OH, and NO₂;    -   d. the compound is not:        -   (1)            N²-2-pyridinyl-6-(3-pyridinyl)-1,3,5-triazine-2,4-diamine;        -   (2)            6-(6-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;        -   (3)            6-(2-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;        -   (4)            N²-(3-chlorophenyl)-6-(2-chloro-4-pyridinyl)-1,3,5-triazine-2,4-diamine;        -   (5)            3-[[4-[4-amino-6-[(3-chlorophenyl)amino]-1,3,5-triazin-2-yl]-2-pyridinyl]amino]-1-propanol;        -   (6)            N-[3-[[4-amino-6-(2-methyl-4-pyrimidinyl)-1,3,5-triazin-2-yl]amino]-4-methylphenyl]-N′-[4-chloro-3-(trifluoromethyl)phenyl]-urea;        -   (7)            N⁴,N^(4′)-diphenyl-[2,2′-bi-1,3,5-triazine]-4,4′,6,6′-tetramine;        -   (8)            6,6′-(2,6-pyridinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine;            or        -   (9)            6,6′-(2,3-pyrazinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine.

In certain embodiments of Formula II, ring A′ is selected from2-chlorophenyl, 2-fluorophenyl, 2-methoxyphenyl, 3-hydroxyphenyl,3-amidophenyl, 3-methylsulfinylphenyl, 3-methylsulfonylphenyl,3-(1-methanol)phenyl, 3-methanaminephenyl, 3-methoxy-2-fluorophenyl,5-methoxy-2-fluorophenyl, 3-hydroxy-2-fluorophenyl,5-hydroxy-2-fluorophenyl, 5-hydroxy-3-fluorophenyl, 3-methanolphenyl,3,5-dihydroxyphenyl, 3-trifluoromethyl-5-chlorophenyl,3-(1-hydoxy-2,2,2-trifluoroethyl)phenyl, 3-(1-hydoxyethyl)phenyl,3-(1-hydoxycyclopropyl)phenyl, 3-hydroxymethyl-5-phenol, pyridin-2-yl,3-fluoropyridin-2-yl, 3-cyanopyridin-2-yl, 3,6-difluoropyridin-2-yl,3-fluoro-6-methoxypyridin-2-yl, 3-fluoro-6-hydroxypyridin-2-yl,3-fluoro-6-aminopyridin-2-yl, 4-fluoro-6-aminopyridin-2-yl,6-propen-1-ylpyridin-2-yl, 6-prop-1-ylpyridin-2-yl,6-methylaminopyridin-2-yl, 3-fluoro-6-trifluoromethylpyridin-2-yl,4-chloro-6-aminopyridin-2-yl, 4-fluoro-6-aminopyridin-2-yl,4-chloro-6-methoxypyridin-2-yl, 6-aminopyridin-3-yl,2-methoxypyridin-3-yl, 6-aminopyridin-2-yl, 6-chloropyridin-2-yl,6-trifluoromethylpyridin-2-yl, 6-difluoromethylpyridin-2-yl,4-(CH₂OH)-6-trifluoromethyl-pyridin-2-yl,4-(CH₂OH)-6-chloro-pyridin-2-yl,6-(1,1-difluoroethyl)-4-fluoropyridin-2-yl,4-trifluoromethylpyrimidin-2-yl, 4-aminopyrimidin-2-yl,6-trifluoromethyl-4-aminopyrimidin-2-yl,4-trifluoromethyl-6-aminopyrimidin-2-yl, 4-aminopyrimidin-2-yl,2-aminopyrimidin-4-yl, 2-aminopyrimidin-5-yl, 4,6-dichloropyridin-2-yl,3,5-dichlorophenyl, 2,6-difluorophenyl, 2-methyloxazol-4-yl,3-methylisoxazol-5-yl, 4-trifluoromethyl-thiazol-2-yl,4-methylthiazol-2-yl and phenyl.

In certain embodiments of Formula II, ring B′ is selected from2-(morpholin-4-yl)pyridin-4-yl, 2-dimethylaminopyridin-4-yl,3-(2-methyoxyethyl)phenyl, 3,5-difluorophenyl, 3-chlorophenyl,3-cyanomethylphenyl, 3-cyanophenyl, 3-(cyclopropylmethyl)phenyl,3-cyclopropylaminosulfonylphenyl, 3-dimethylaminosulfonylphenyl,3-ethylsulfonylphenyl, 3-fluorophenyl, 3-methylsulfonylphenyl,4-fluorophenyl, 3-(1-hydroxyisopropyl)phenyl,3-methylsulfonyl-5-chlorophenyl, 3-methylsulfonyl-5-fluorophenyl,3-(N-2,2,2,-trifluoroethylaminosulfonyl)phenyl,3-(N-cyclopropyl)benzamide, 5-chloropyridin-3-yl, 5-cyanopyridin-3-yl,5-cyanopyridin-3-yl, 5-cyanopyridin-4-yl, 5-fluoropyridin-3-yl,2-(1-hydroxyisopropyl)pyridin-4-yl, 5-trifluoromethypyridin-3-yl,2-trifluoromethylpyridin-4-yl, 2-difluoromethylpyridin-4-yl,2-chloropyridin-4-yl, 6-chloropyridin-4-yl, 6-cyanopyridin-4-yl,2-cyanopyridin-4-yl, 6-cyclopropylpyridin-4-yl, 6-ethoxypyridin-4-yl,6-fluoropyridin-3-yl, 2-fluoropyridin-4-yl, 5,6-difluoropyridin-3-yl,6-fluoropyridin-4-yl, 6-methylpyridin-4-yl,2-difluoromethylpyridin-4-yl, 6-trifluoromethylpyridin-4-yl,2-(1-methoxycyclopropyl)pyridin-4-yl, 2-cyclopropylpyridin-4-yl,2-(propan-1-one)pyridin-4-yl, 2-(1-methylcyclopropyl)pyridin-4-yl,2-(1-cyanocyclopropyl)pyridin-4-yl, 2-(1-cyanoisopropyl)pyridin-4-yl,isoxazol-4-yl, phenyl, pyridin-4-yl, picolinat-2-yl, pyrimidin-5-yl,1-propylpyrazol-4-yl, 6-methyl-pyridazin-4-yl, and thiazol-5-yl.

Further embodiments provided herein include combinations of one or moreof the particular embodiments set forth above.

In another embodiment, the compound is selected from any one of thecompounds set forth in Table 1, below.

TABLE 1 Representative Compounds Cmpd No Structure 114

129

147

154

155

156

169

184

185

193

196

197

199

200

202

224

226

227

228

229

230

231

246

247

266

270

281

288

289

290

292

293

298

299

301

302

303

308

309

310

311

312

313

314

315

316

318

319

320

321

322

323

325

326

327

328

329

330

331

332

334

337

340

343

344

345

346

350

353

354

355

356

357

358

359

360

361

363

364

365

366

367

368

369

371

377

378

379

380

381

382

383

386

387

388

389

392

393

395

397

398

399

400

401

403

410

450

454

455

456

458

459

460

461

462

463

464

467

468

469

470

474

477

481

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

499

500

501

502

503

511

514

515

516

518

519

521

522

528

535

536

537

538

540

541

543

551

554

555

557

559

560

561

563

567

570

572

574

576

581

582

583

586

592

594

596

598

599

604

605

606

607

608

609

610

611

612

614

618

621

622

623

624

627

629

630

632

633

634

635

639

640

644

645

647

648

649

650

651

652

653

654

655

657

658

662

663

664

665

666

670

671

672

673

674

675

676

678

682

683

686

687

691

696

697

Included are methods for making compounds of Formula I or a compound ofany one of the embodiments described herein comprising reacting

with NH₃. In some embodiments, the preceding methods comprise step (1)reacting

with

to give

and step (2) reacting

with NH₃.

The compounds of one aspect of this invention may contain one or moreasymmetric centers and thus occur as racemates, racemic mixtures,scalemic mixtures, and diastereomeric mixtures, as well as singleenantiomers or individual stereoisomers that are substantially free fromanother possible enantiomer or stereoisomer. The term “substantiallyfree of other stereoisomers” as used herein means a preparation enrichedin a compound having a selected stereochemistry at one or more selectedstereocenters by at least about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%,96%, 97%, 98%, or 99%. The term “enriched” means that at least thedesignated percentage of a preparation is the compound having a selectedstereochemistry at one or more selected stereocenters. Methods ofobtaining or synthesizing an individual enantiomer or stereoisomer for agiven compound are known in the art and may be applied as practicable tofinal compounds or to starting material or intermediates.

In certain embodiments, the compound of Formula I or II is enriched fora structure or structures having a selected stereochemistry at one ormore carbon atoms. For example, the compound is enriched in the specificstereoisomer by at least about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%,96%, 97%, 98%, or 99%.

The compounds of Formula I or II may also comprise one or more isotopicsubstitutions. For example, H may be in any isotopic form, including ¹H,²H (D or deuterium), and ³H (T or tritium); C may be in any isotopicform, including ¹¹C, ¹²C, ¹³C, and ¹⁴C; N may be in any isotopic form,including ¹³N, ¹⁴N and ¹⁵N; O may be in any isotopic form, including¹⁵O, ¹⁶O and ¹⁸O; F may be in any isotopic form, including ¹⁸F; and thelike. For example, the compound is enriched in a specific isotopic formof H, C, N, O and/or F by at least about 60%, 65%, 70%, 75%, 80%, 85%,90%, 95%, 96%, 97%, 98%, or 99%.

Unless otherwise indicated when a disclosed compound is named ordepicted by a structure without specifying the stereochemistry and hasone or more chiral centers, it is understood to represent all possiblestereoisomers of the compound.

The compounds of one aspect of this invention may also be represented inmultiple tautomeric forms, in such instances, one aspect of theinvention expressly includes all tautomeric forms of the compoundsdescribed herein, even though only a single tautomeric form may berepresented (e.g., alkylation of a ring system may result in alkylationat multiple sites, one aspect of the invention expressly includes allsuch reaction products; and keto-enol tautomers). All such isomericforms of such compounds are expressly included herein.

It may be convenient or desirable to prepare, purify, and/or handle acorresponding salt of the active compound, for example, apharmaceutically-acceptable salt. Examples of pharmaceuticallyacceptable salts are discussed in Berge et al., 1977, “PharmaceuticallyAcceptable Salts.” J. Pharm. Sci. Vol. 66, pp. 1-19.

For example, if the compound is anionic, or has a functional group whichmay be anionic (e.g., —COOH may be —COO⁻), then a salt may be formedwith a suitable cation. Examples of suitable inorganic cations include,but are not limited to, alkali metal ions such as Na⁺ and K⁺, alkalineearth cations such as Ca²⁺ and Mg²⁺, and other cations such as Al³⁺.Examples of suitable organic cations include, but are not limited to,ammonium ion (i.e., NH₄ ⁺) and substituted ammonium ions (e.g., NH₃R⁺,NH₂R²⁺, NHR³⁺, NR⁴⁺). Examples of some suitable substituted ammoniumions are those derived from: ethylamine, diethylamine,dicyclohexylamine, triethylamine, butylamine, ethylenediamine,ethanolamine, diethanolamine, piperazine, benzylamine,phenylbenzylamine, choline, meglumine, and tromethamine, as well asamino acids, such as lysine and arginine. An example of a commonquaternary ammonium ion is N(CH₃)₄ ⁺.

If the compound is cationic, or has a functional group that may becationic (e.g., —NH₂ may be —NH₃ ⁺), then a salt may be formed with asuitable anion. Examples of suitable inorganic anions include, but arenot limited to, those derived from the following inorganic acids:hydrochloric, hydrobromic, hydroiodic, sulfuric, sulfurous, nitric,nitrous, phosphoric, and phosphorous.

Examples of suitable organic anions include, but are not limited to,those derived from the following organic acids: 2-acetyoxybenzoic,acetic, ascorbic, aspartic, benzoic, camphorsulfonic, cinnamic, citric,edetic, ethanedisulfonic, ethanesulfonic, fumaric, glucoheptonic,gluconic, glutamic, glycolic, hydroxymaleic, hydroxynaphthalenecarboxylic, isethionic, lactic, lactobionic, lauric, maleic, malic,methanesulfonic, mucic, oleic, oxalic, palmitic, pamoic, pantothenic,phenylacetic, phenylsulfonic, propionic, pyruvic, salicylic, stearic,succinic, sulfanilic, tartaric, toluenesulfonic, and valeric. Mesylatesof each compound in Table 1 are explicitly included herein. Examples ofsuitable polymeric organic anions include, but are not limited to, thosederived from the following polymeric acids: tannic acid, carboxymethylcellulose.

The compounds provided herein therefore include the compoundsthemselves, as well as their salts, hydrates and their prodrugs, ifapplicable. The compounds provided herein may be modified and convertedto prodrugs by appending appropriate functionalities to enhance selectedbiological properties, e.g., targeting to a particular tissue. Suchmodifications (i.e., prodrugs) are known in the art and include thosewhich increase biological penetration into a given biologicalcompartment (e.g., blood, lymphatic system, central nervous system),increase oral availability, increase solubility to allow administrationby injection, alter metabolism and alter rate of excretion. Examples ofprodrugs include esters (e.g., phosphates, amino acid (e.g., valine)esters), carbamates and other pharmaceutically acceptable derivatives,which, upon administration to a subject, are capable of providing activecompounds. Calcium and sodium phosphates of each compound in Table 1, ifapplicable, are explicitly included herein. Amino acid (e.g., valine)esters of each compound in Table 1, if applicable, are explicitlyincluded herein.

Compositions and Routes of Administration

The compounds utilized in the methods described herein may be formulatedtogether with a pharmaceutically acceptable carrier or adjuvant intopharmaceutically acceptable compositions prior to be administered to asubject. In another embodiment, such pharmaceutically acceptablecompositions further comprise additional therapeutic agents in amountseffective for achieving a modulation of disease or disease symptoms,including those described herein.

The term “pharmaceutically acceptable carrier or adjuvant” refers to acarrier or adjuvant that may be administered to a subject, together witha compound of one aspect of this invention, and which does not destroythe pharmacological activity thereof and is nontoxic when administeredin doses sufficient to deliver a therapeutic amount of the compound.

Pharmaceutically acceptable carriers, adjuvants and vehicles that may beused in the pharmaceutical compositions of one aspect of this inventioninclude, but are not limited to, ion exchangers, alumina, aluminumstearate, lecithin, self-emulsifying drug delivery systems (SEDDS) suchas d-α-tocopherol polyethyleneglycol 1000 succinate, surfactants used inpharmaceutical dosage forms such as Tweens or other similar polymericdelivery matrices, serum proteins, such as human serum albumin, buffersubstances such as phosphates, glycine, sorbic acid, potassium sorbate,partial glyceride mixtures of saturated vegetable fatty acids, water,salts or electrolytes, such as protamine sulfate, disodium hydrogenphosphate, potassium hydrogen phosphate, sodium chloride, zinc salts,colloidal silica, magnesium trisilicate, polyvinyl pyrrolidone,cellulose-based substances, polyethylene glycol, sodiumcarboxymethylcellulose, polyacrylates, waxes,polyethylene-polyoxypropylene-block polymers, polyethylene glycol andwool fat. Cyclodextrins such as α-, β-, and γ-cyclodextrin, orchemically modified derivatives such as hydroxyalkylcyclodextrins,including 2- and 3-hydroxypropyl-β-cyclodextrins, or other solubilizedderivatives may also be advantageously used to enhance delivery ofcompounds of the formulae described herein.

The pharmaceutical compositions of one aspect of this invention may beadministered orally, parenterally, by inhalation spray, topically,rectally, nasally, buccally, vaginally or via an implanted reservoir,preferably by oral administration or administration by injection. Thepharmaceutical compositions of one aspect of this invention may containany conventional non-toxic pharmaceutically-acceptable carriers,adjuvants or vehicles. In some cases, the pH of the formulation may beadjusted with pharmaceutically acceptable acids, bases or buffers toenhance the stability of the formulated compound or its delivery form.The term parenteral as used herein includes subcutaneous,intracutaneous, intravenous, intramuscular, intraarticular,intraarterial, intrasynovial, intrasternal, intrathecal, intralesionaland intracranial injection or infusion techniques.

The pharmaceutical compositions may be in the form of a sterileinjectable preparation, for example, as a sterile injectable aqueous oroleaginous suspension. This suspension may be formulated according totechniques known in the art using suitable dispersing or wetting agents(such as, for example, Tween 80) and suspending agents. The sterileinjectable preparation may also be a sterile injectable solution orsuspension in a non-toxic parenterally acceptable diluent or solvent,for example, as a solution in 1,3-butanediol. Among the acceptablevehicles and solvents that may be employed are mannitol, water, Ringer'ssolution and isotonic sodium chloride solution. In addition, sterile,fixed oils are conventionally employed as a solvent or suspendingmedium. For this purpose, any bland fixed oil may be employed includingsynthetic mono- or diglycerides. Fatty acids, such as oleic acid and itsglyceride derivatives are useful in the preparation of injectables, asare natural pharmaceutically-acceptable oils, such as olive oil orcastor oil, especially in their polyoxyethylated versions. These oilsolutions or suspensions may also contain a long-chain alcohol diluentor dispersant, or carboxymethyl cellulose or similar dispersing agentswhich are commonly used in the formulation of pharmaceuticallyacceptable dosage forms such as emulsions and or suspensions. Othercommonly used surfactants such as Tweens or Spans and/or other similaremulsifying agents or bioavailability enhancers which are commonly usedin the manufacture of pharmaceutically acceptable solid, liquid, orother dosage forms may also be used for the purposes of formulation.

The pharmaceutical compositions of one aspect of this invention may beorally administered in any orally acceptable dosage form including, butnot limited to, capsules, tablets, emulsions and aqueous suspensions,dispersions and solutions. In the case of tablets for oral use, carrierswhich are commonly used include lactose and corn starch. Lubricatingagents, such as magnesium stearate, are also typically added. For oraladministration in a capsule form, useful diluents include lactose anddried corn starch. When aqueous suspensions and/or emulsions areadministered orally, the active ingredient may be suspended or dissolvedin an oily phase is combined with emulsifying and/or suspending agents.If desired, certain sweetening and/or flavoring and/or coloring agentsmay be added.

The pharmaceutical compositions of one aspect of this invention may alsobe administered in the form of suppositories for rectal administration.These compositions can be prepared by mixing a compound of one aspect ofthis invention with a suitable non-irritating excipient which is solidat room temperature but liquid at the rectal temperature and thereforewill melt in the rectum to release the active components. Such materialsinclude, but are not limited to, cocoa butter, beeswax and polyethyleneglycols.

Topical administration of the pharmaceutical compositions of one aspectof this invention is useful when the desired treatment involves areas ororgans readily accessible by topical application. For applicationtopically to the skin, the pharmaceutical composition should beformulated with a suitable ointment containing the active componentssuspended or dissolved in a carrier. Carriers for topical administrationof the compounds of one aspect of this invention include, but are notlimited to, mineral oil, liquid petroleum, white petroleum, propyleneglycol, polyoxyethylene polyoxypropylene compound, emulsifying wax andwater. Alternatively, the pharmaceutical composition can be formulatedwith a suitable lotion or cream containing the active compound suspendedor dissolved in a carrier with suitable emulsifying agents. Suitablecarriers include, but are not limited to, mineral oil, sorbitanmonostearate, polysorbate 60, cetyl esters wax, cetearyl alcohol,2-octyldodecanol, benzyl alcohol and water. The pharmaceuticalcompositions of one aspect of this invention may also be topicallyapplied to the lower intestinal tract by rectal suppository formulationor in a suitable enema formulation. Topically-transdermal patches arealso included in one aspect of this invention.

The pharmaceutical compositions of one aspect of this invention may beadministered by nasal aerosol or inhalation. Such compositions areprepared according to techniques well-known in the art of pharmaceuticalformulation and may be prepared as solutions in saline, employing benzylalcohol or other suitable preservatives, absorption promoters to enhancebioavailability, fluorocarbons, and/or other solubilizing or dispersingagents known in the art.

When the compositions of one aspect of this invention comprise acombination of a compound of the formulae described herein and one ormore additional therapeutic or prophylactic agents, both the compoundand the additional agent should be present at dosage levels of betweenabout 1 to 100%, and more preferably between about 5 to 95% of thedosage normally administered in a monotherapy regimen. The additionalagents may be administered separately, as part of a multiple doseregimen, from the compounds of one aspect of this invention.Alternatively, those agents may be part of a single dosage form, mixedtogether with the compounds of one aspect of this invention in a singlecomposition.

The compounds described herein can, for example, be administered byinjection, intravenously, intraarterially, subdermally,intraperitoneally, intramuscularly, or subcutaneously; or orally,buccally, nasally, transmucosally, topically, in an ophthalmicpreparation, or by inhalation, with a dosage ranging from about 0.5 toabout 100 mg/kg of body weight, alternatively dosages between 1 mg and1000 mg/dose, every 4 to 120 hours, or according to the requirements ofthe particular drug. The methods herein contemplate administration of aneffective amount of compound or compound composition to achieve thedesired or stated effect. Typically, the pharmaceutical compositions ofone aspect of this invention will be administered from about 1 to about6 times per day or alternatively, as a continuous infusion. Suchadministration can be used as a chronic or acute therapy. The amount ofactive ingredient that may be combined with the carrier materials toproduce a single dosage form will vary depending upon the host treatedand the particular mode of administration. A typical preparation willcontain from about 5% to about 95% active compound (w/w). Alternatively,such preparations contain from about 20% to about 80% active compound.

Lower or higher doses than those recited above may be required. Specificdosage and treatment regimens for any particular subject will dependupon a variety of factors, including the activity of the specificcompound employed, the age, body weight, general health status, sex,diet, time of administration, rate of excretion, drug combination, theseverity and course of the disease, condition or symptoms, the subject'sdisposition to the disease, condition or symptoms, and the judgment ofthe treating physician.

Upon improvement of a subject's condition, a maintenance dose of acompound, composition or combination of one aspect of this invention maybe administered, if necessary. Subsequently, the dosage or frequency ofadministration, or both, may be reduced, as a function of the symptoms,to a level at which the improved condition is retained when the symptomshave been alleviated to the desired level. Subjects may, however,require intermittent treatment on a long-term basis upon any recurrenceof disease symptoms.

The pharmaceutical compositions described above comprising a compound ofStructural Formula I or II or a compound described in any one of theembodiments herein, may further comprise another therapeutic agentuseful for treating cancer.

Methods of Use

The inhibitory activities of the compounds provided herein against IDH2mutants (e.g., IDH2R140Q and IDH2R172K) can be tested by methodsdescribed in Example A or analogous methods.

Provided is a method for inhibiting a mutant IDH2 activity comprisingcontacting a subject in need thereof with a compound of StructuralFormula I or II, a compound described in any one of the embodimentsherein, or a pharmaceutically acceptable salt thereof. In oneembodiment, the cancer to be treated is characterized by a mutant alleleof IDH2 wherein the IDH2 mutation results in a new ability of the enzymeto catalyze the NAPH-dependent reduction of α-ketoglutarate toR(−)-2-hydroxyglutarate in a subject. In one aspect of this embodiment,the mutant IDH2 has an R140X mutation. In another aspect of thisembodiment, the R140X mutation is a R140Q mutation. In another aspect ofthis embodiment, the R140X mutation is a R140W mutation. In anotheraspect of this embodiment, the R140X mutation is a R140L mutation. Inanother aspect of this embodiment, the mutant IDH2 has an R172Xmutation. In another aspect of this embodiment, the R172X mutation is aR172K mutation. In another aspect of this embodiment, the R172X mutationis a R172G mutation.

Also provided are methods of treating a cancer characterized by thepresence of a mutant allele of IDH2 comprising the step of administeringto subject in need thereof (a) a compound of Structural Formula I or II,a compound described in any one of the embodiments herein, or apharmaceutically acceptable salt thereof, or (b) a pharmaceuticalcomposition comprising (a) and a pharmaceutically acceptable carrier.

In one embodiment, the cancer to be treated is characterized by a mutantallele of IDH2 wherein the IDH2 mutation results in a new ability of theenzyme to catalyze the NAPH-dependent reduction of α-ketoglutarate toR(−)-2-hydroxyglutarate in a patient. In one aspect of this embodiment,the mutant IDH2 has an R140X mutation. In another aspect of thisembodiment, the R140X mutation is a R140Q mutation. In another aspect ofthis embodiment, the R140X mutation is a R140W mutation. In anotheraspect of this embodiment, the R140X mutation is a R140L mutation. Inanother aspect of this embodiment, the mutant IDH2 has an R172Xmutation. In another aspect of this embodiment, the R172X mutation is aR172K mutation. In another aspect of this embodiment, the R172X mutationis a R172G mutation. A cancer can be analyzed by sequencing cell samplesto determine the presence and specific nature of (e.g., the changedamino acid present at) a mutation at amino acid 140 and/or 172 of IDH2.

Without being bound by theory, applicants believe that mutant alleles ofIDH2 wherein the IDH2 mutation results in a new ability of the enzyme tocatalyze the NAPH-dependent reduction of α-ketoglutarate toR(−)-2-hydroxyglutarate, and in particular R140Q and/or R172K mutationsof IDH2, characterize a subset of all types of cancers, without regardto their cellular nature or location in the body. Thus, the compoundsand methods of one aspect of this invention are useful to treat any typeof cancer that is characterized by the presence of a mutant allele ofIDH2 imparting such activity and in particular an IDH2 R140Q and/orR172K mutation.

In one aspect of this embodiment, the efficacy of cancer treatment ismonitored by measuring the levels of 2HG in the subject. Typicallylevels of 2HG are measured prior to treatment, wherein an elevated levelis indicated for the use of the compound of Formula I or II or acompound described in any one of the embodiments described herein totreat the cancer. Once the elevated levels are established, the level of2HG is determined during the course of and/or following termination oftreatment to establish efficacy. In certain embodiments, the level of2HG is only determined during the course of and/or following terminationof treatment. A reduction of 2HG levels during the course of treatmentand following treatment is indicative of efficacy. Similarly, adetermination that 2HG levels are not elevated during the course of orfollowing treatment is also indicative of efficacy. Typically, the these2HG measurements will be utilized together with other well-knowndeterminations of efficacy of cancer treatment, such as reduction innumber and size of tumors and/or other cancer-associated lesions,improvement in the general health of the subject, and alterations inother biomarkers that are associated with cancer treatment efficacy.

2HG can be detected in a sample by LC/MS. The sample is mixed 80:20 withmethanol, and centrifuged at 3,000 rpm for 20 minutes at 4 degreesCelsius. The resulting supernatant can be collected and stored at −80degrees Celsius prior to LC-MS/MS to assess 2-hydroxyglutarate levels. Avariety of different liquid chromatography (LC) separation methods canbe used. Each method can be coupled by negative electrospray ionization(ESI, −3.0 kV) to triple-quadrupole mass spectrometers operating inmultiple reaction monitoring (MRM) mode, with MS parameters optimized oninfused metabolite standard solutions. Metabolites can be separated byreversed phase chromatography using 10 mM tributyl-amine as an ionpairing agent in the aqueous mobile phase, according to a variant of apreviously reported method (Luo et al. J Chromatogr A 1147, 153-64,2007). One method allows resolution of TCA metabolites: t=0, 50% B; t=5,95% B; t=7, 95% B; t=8, 0% B, where B refers to an organic mobile phaseof 100% methanol. Another method is specific for 2-hydroxyglutarate,running a fast linear gradient from 50%-95% B (buffers as defined above)over 5 minutes. A Synergi Hydro-RP, 100 mm×2 mm, 2.1 μm particle size(Phenomonex) can be used as the column, as described above. Metabolitescan be quantified by comparison of peak areas with pure metabolitestandards at known concentration. Metabolite flux studies from¹³C-glutamine can be performed as described, e.g., in Munger et al. NatBiotechnol 26, 1179-86, 2008.

In one embodiment 2HG is directly evaluated.

In another embodiment a derivative of 2HG formed in process ofperforming the analytic method is evaluated. By way of example such aderivative can be a derivative formed in MS analysis. Derivatives caninclude a salt adduct, e.g., a Na adduct, a hydration variant, or ahydration variant which is also a salt adduct, e.g., a Na adduct, e.g.,as formed in MS analysis.

In another embodiment a metabolic derivative of 2HG is evaluated.Examples include species that build up or are elevated, or reduced, as aresult of the presence of 2HG, such as glutarate or glutamate that willbe correlated to 2HG, e.g., R-2HG.

Exemplary 2HG derivatives include dehydrated derivatives such as thecompounds provided below or a salt adduct thereof:

In one embodiment the cancer is a tumor wherein at least 30, 40, 50, 60,70, 80 or 90% of the tumor cells carry an IDH2 mutation, and inparticular an IDH2 R140Q, R140W, or R140L and/or R172K or R172Gmutation, at the time of diagnosis or treatment.

In another embodiment, one aspect of the invention provides a method oftreating a cancer selected from glioblastoma (glioma), myelodysplasticsyndrome (MDS), myeloproliferative neoplasm (MPN), acute myelogenousleukemia (AML), sarcoma, melanoma, non-small cell lung cancer,chondrosarcoma, cholangiocarcinomas or angioimmunoblastic lymphoma in apatient by administering to the patient a compound of Formula I orFormula II in an amount effective to treat the cancer. In a morespecific embodiment the cancer to be treated is glioma, myelodysplasticsyndrome (MDS), myeloproliferative neoplasm (MPN), acute myelogenousleukemia (AML), melanoma, chondrosarcoma, or angioimmunoblasticnon-Hodgkin's lymphoma (NHL).

In another embodiment, the methods described herein are used to treatglioma (glioblastoma), acute myelogenous leukemia, sarcoma, melanoma,non-small cell lung cancer (NSCLC), cholangiocarcinomas (e.g.,intrahepatic cholangiocarcinoma (IHCC)), chondrosarcoma, myelodysplasticsyndromes (MDS), myeloproliferative neoplasm (MPN), prostate cancer,chronic myelomonocytic leukemia (CMML), B-acute lymphoblastic leukemias(B-ALL), B-acute lymphoblastic leukemias (B-ALL), myeloid sarcoma,multiple myeloma, lymphoma colon cancer, or angio-immunoblasticnon-Hodgkin's lymphoma (NHL) in a patient. In another embodiment, thecancer to be treated is an advanced hematologic malignancy selected fromlymphoma (e.g., Non-Hodgkin lymphoma (NHL) such B-cell lymphoma (e.g.,Burkitt lymphoma, chronic lymphocytic leukemia/small lymphocyticlymphoma (CLL/SLL), diffuse large B-cell lymphoma, follicular lymphoma,immunoblastic large cell lymphoma, precursor B-lymphoblastic lymphoma,and mantle cell lymphoma) and T-cell lymphoma (e.g., mycosis fungoides,anaplastic large cell lymphoma, and precursor T-lymphoblastic lymphoma).

2HG is known to accumulate in the inherited metabolic disorder2-hydroxyglutaric aciduria. This disease is caused by deficiency in theenzyme 2-hydroxyglutarate dehydrogenase, which converts 2HG to α-KG(Struys, E. A. et al. Am J Hum Genet 76, 358-60 (2005)). Patients with2-hydroxyglutarate dehydrogenase deficiencies accumulate 2HG in thebrain as assessed by MRI and CSF analysis, develop leukoencephalopathy,and have an increased risk of developing brain tumors (Aghili, M.,Zahedi, F. & Rafiee, J Neurooncol 91, 233-6 (2009); Kolker, S.,Mayatepek, E. & Hoffmann, G. F. Neuropediatrics 33, 225-31 (2002);Wajner, M., Latini, A., Wyse, A. T. & Dutra-Filho, C. S. J Inherit MetabDis 27, 427-48 (2004)). Furthermore, elevated brain levels of 2HG resultin increased ROS levels (Kolker, S. et al. Eur J Neurosci 16, 21-8(2002); Latini, A. et al. Eur J Neurosci 17, 2017-22 (2003)),potentially contributing to an increased risk of cancer. The ability of2HG to act as an NMDA receptor agonist may contribute to this effect(Kolker, S. et al. Eur J Neurosci 16, 21-8 (2002)). 2HG may also betoxic to cells by competitively inhibiting glutamate and/or αKGutilizing enzymes. These include transaminases which allow utilizationof glutamate nitrogen for amino and nucleic acid biosynthesis, andαKG-dependent prolyl hydroxylases such as those which regulateHif1-alpha levels.

Thus, according to another embodiment, one aspect of the inventionprovides a method of treating 2-hydroxyglutaric aciduria, particularlyD-2-hydroxyglutaric aciduria, in a patient by administering to thepatient a compound of Structural Formula I or II or a compound describedin any one of the embodiments described herein.

Treatment methods described herein can additionally comprise variousevaluation steps prior to and/or following treatment with a compound ofStructural Formula I or II or a compound described in any one of theembodiments described herein.

In one embodiment, prior to and/or after treatment with a compound ofStructural Formula I or II or a compound described in any one of theembodiments described herein, the method further comprises the step ofevaluating the growth, size, weight, invasiveness, stage and/or otherphenotype of the cancer.

In one embodiment, prior to and/or after treatment with a compound ofFormula I or II or a compound described in any one of the embodimentsdescribed herein, the method further comprises the step of evaluatingthe IDH2 genotype of the cancer. This may be achieved by ordinarymethods in the art, such as DNA sequencing, immuno analysis, and/orevaluation of the presence, distribution or level of 2HG.

In one embodiment, prior to and/or after treatment with a compound ofFormula I or II or a compound described in any one of the embodimentsdescribed herein, the method further comprises the step of determiningthe 2HG level in the subject. This may be achieved by spectroscopicanalysis, e.g., magnetic resonance-based analysis, e.g., MRI and/or MRSmeasurement, sample analysis of bodily fluid, such as serum, bonemarrow, blood, urine, or spinal cord fluid analysis, or by analysis ofsurgical material, e.g., by mass-spectroscopy.

Combination Therapies

In some embodiments, the methods described herein comprise theadditional step of co-administering to a subject in need thereof asecond therapy e.g., an additional cancer therapeutic agent or anadditional cancer treatment. Exemplary additional cancer therapeuticagents include for example, chemotherapy, targeted therapy, antibodytherapies, immunotherapy, and hormonal therapy. Additional cancertreatments include, for example: surgery, and radiation therapy.Examples of each of these treatments are provided below.

The term “co-administering” as used herein with respect to an additionalcancer therapeutic agents means that the additional cancer therapeuticagent may be administered together with a compound of one aspect of thisinvention as part of a single dosage form (such as a composition of oneaspect of this invention comprising a compound of one aspect of theinvention and an second therapeutic agent as described above) or asseparate, multiple dosage forms. Alternatively, the additional cancertherapeutic agent may be administered prior to, consecutively with, orfollowing the administration of a compound of one aspect of thisinvention. In such combination therapy treatment, both the compounds ofone aspect of this invention and the second therapeutic agent(s) areadministered by conventional methods. The administration of acomposition of one aspect of this invention, comprising both a compoundof one aspect of the invention and a second therapeutic agent, to asubject does not preclude the separate administration of that sametherapeutic agent, any other second therapeutic agent or any compound ofone aspect of this invention to said subject at another time during acourse of treatment. The term “co-administering” as used herein withrespect to an additional cancer treatment means that the additionalcancer treatment may occur prior to, consecutively with, concurrentlywith or following the administration of a compound of one aspect of thisinvention.

In some embodiments, the additional cancer therapeutic agent is achemotherapy agent. Examples of chemotherapeutic agents used in cancertherapy include, for example, antimetabolites (e.g., folic acid, purine,and pyrimidine derivatives), alkylating agents (e.g., nitrogen mustards,nitrosoureas, platinum, alkyl sulfonates, hydrazines, triazenes,aziridines, spindle poison, cytotoxic agents, topoisomerase inhibitorsand others), and hypomethylating agents (e.g., decitabine(5-aza-deoxycytidine), zebularine, isothiocyanates, azacitidine(5-azacytidine), 5-flouro-2′-deoxycytidine, 5,6-dihydro-5-azacytidineand others). Exemplary agents include Aclarubicin, Actinomycin,Alitretinoin, Altretamine, Aminopterin, Aminolevulinic acid, Amrubicin,Amsacrine, Anagrelide, Arsenic trioxide, Asparaginase, Atrasentan,Belotecan, Bexarotene, bendamustine, Bleomycin, Bortezomib, Busulfan,Camptothecin, Capecitabine, Carboplatin, Carboquone, Carmofur,Carmustine, Celecoxib, Chlorambucil, Chlormethine, Cisplatin,Cladribine, Clofarabine, Crisantaspase, Cyclophosphamide, Cytarabine,Dacarbazine, Dactinomycin, Daunorubicin, Decitabine, Demecolcine,Docetaxel, Doxorubicin, Efaproxiral, Elesclomol, Elsamitrucin,Enocitabine, Epirubicin, Estramustine, Etoglucid, Etoposide,Floxuridine, Fludarabine, Fluorouracil (5FU), Fotemustine, Gemcitabine,Gliadel implants, Hydroxycarbamide, Hydroxyurea, Idarubicin, Ifosfamide,Irinotecan, Irofulven, Ixabepilone, Larotaxel, Leucovorin, Liposomaldoxorubicin, Liposomal daunorubicin, Lonidamine, Lomustine, Lucanthone,Mannosulfan, Masoprocol, Melphalan, Mercaptopurine, Mesna, Methotrexate,Methyl aminolevulinate, Mitobronitol, Mitoguazone, Mitotane, Mitomycin,Mitoxantrone, Nedaplatin, Nimustine, Oblimersen, Omacetaxine, Ortataxel,Oxaliplatin, Paclitaxel, Pegaspargase, Pemetrexed, Pentostatin,Pirarubicin, Pixantrone, Plicamycin, Porfimer sodium, Prednimustine,Procarbazine, Raltitrexed, Ranimustine, Rubitecan, Sapacitabine,Semustine, Sitimagene ceradenovec, Strataplatin, Streptozocin,Talaporfin, Tegafur-uracil, Temoporfin, Temozolomide, Teniposide,Tesetaxel, Testolactone, Tetranitrate, Thiotepa, Tiazofurine,Tioguanine, Tipifarnib, Topotecan, Trabectedin, Triaziquone,Triethylenemelamine, Triplatin, Tretinoin, Treosulfan, Trofosfamide,Uramustine, Valrubicin, Verteporfin, Vinblastine, Vincristine,Vindesine, Vinflunine, Vinorelbine, Vorinostat, Zorubicin, and othercytostatic or cytotoxic agents described herein.

Because some drugs work better together than alone, two or more drugsare often given at the same time. Often, two or more chemotherapy agentsare used as combination chemotherapy.

In some embodiments, the additional cancer therapeutic agent is adifferentiation agent. Such differentiation agent includes retinoids(such as all-trans-retinoic acid (ATRA), 9-cis retinoic acid,13-cis-retinoic acid (13-cRA) and 4-hydroxy-phenretinamide (4-HPR));arsenic trioxide; histone deacetylase inhibitors HDACs (such asazacytidine (Vidaza) and butyrates (e.g., sodium phenylbutyrate));hybrid polar compounds (such as hexamethylene bisacetamide ((HMBA));vitamin D; and cytokines (such as colony-stimulating factors includingG-CSF and GM-CSF, and interferons).

In some embodiments the additional cancer therapeutic agent is atargeted therapy agent. Targeted therapy constitutes the use of agentsspecific for the deregulated proteins of cancer cells. Small moleculetargeted therapy drugs are generally inhibitors of enzymatic domains onmutated, overexpressed, or otherwise critical proteins within the cancercell. Prominent examples are the tyrosine kinase inhibitors such asAxitinib, Bosutinib, Cediranib, dasatinib, erlotinib, imatinib,gefitinib, lapatinib, Lestaurtinib, Nilotinib, Semaxanib, Sorafenib,Sunitinib, and Vandetanib, and also cyclin-dependent kinase inhibitorssuch as Alvocidib and Seliciclib. Monoclonal antibody therapy is anotherstrategy in which the therapeutic agent is an antibody whichspecifically binds to a protein on the surface of the cancer cells.Examples include the anti-HER2/neu antibody trastuzumab (HERCEPTIN®)typically used in breast cancer, and the anti-CD20 antibody rituximaband Tositumomab typically used in a variety of B-cell malignancies.Other exemplary antibodies include Cetuximab, Panitumumab, Trastuzumab,Alemtuzumab, Bevacizumab, Edrecolomab, and Gemtuzumab. Exemplary fusionproteins include Aflibercept and Denileukin diftitox. In someembodiments, the targeted therapy can be used in combination with acompound described herein, e.g., a biguanide such as metformin orphenformin, preferably phenformin.

Targeted therapy can also involve small peptides as “homing devices”which can bind to cell surface receptors or affected extracellularmatrix surrounding the tumor. Radionuclides which are attached to thesepeptides (e.g., RGDs) eventually kill the cancer cell if the nuclidedecays in the vicinity of the cell. An example of such therapy includesBEXXAR®.

In some embodiments, the additional cancer therapeutic agent is animmunotherapy agent. Cancer immunotherapy refers to a diverse set oftherapeutic strategies designed to induce the subject's own immunesystem to fight the tumor. Contemporary methods for generating an immuneresponse against tumors include intravesicular BCG immunotherapy forsuperficial bladder cancer, and use of interferons and other cytokinesto induce an immune response in renal cell carcinoma and melanomasubjects.

Allogeneic hematopoietic stem cell transplantation can be considered aform of immunotherapy, since the donor's immune cells will often attackthe tumor in a graft-versus-tumor effect. In some embodiments, theimmunotherapy agents can be used in combination with a compound orcomposition described herein.

In some embodiments, the additional cancer therapeutic agent is ahormonal therapy agent. The growth of some cancers can be inhibited byproviding or blocking certain hormones. Common examples ofhormone-sensitive tumors include certain types of breast and prostatecancers. Removing or blocking estrogen or testosterone is often animportant additional treatment. In certain cancers, administration ofhormone agonists, such as progestogens may be therapeuticallybeneficial. In some embodiments, the hormonal therapy agents can be usedin combination with a compound or a composition described herein.

Other possible additional therapeutic modalities include imatinib, genetherapy, peptide and dendritic cell vaccines, synthetic chlorotoxins,and radiolabeled drugs and antibodies.

EXAMPLES Abbreviations

anhy.-anhydrous δ-chemical shift aq.-aqueous J-coupling constantmin-minute(s) s-singlet mL-milliliter d-doublet mmol-millimole(s)t-triplet mol-mole(s) q-quartet MS-mass spectrometry m-multipletNMR-nuclear magnetic resonance br-broad TLC-thin layer chromatographyqd-quartet of doublets HPLC-high-performance liquid dquin-doublet ofquintets chromatography dd-doublet of doublets Hz-hertz dt-doublet oftriplets CHCl₃-chloroform NaHCO₃-sodium bicarbonate DCM-dichloromethaneLiHMDS-lithium DMF-dimethylformamide hexamethyldisilylamide Et₂O-diethylether NaHMDS-sodium EtOH-ethyl alcohol hexamethyldisilylamideEtOAc-ethyl acetate LAH-lithium aluminum hydride MeOH-methyl alcoholNaBH₄-sodium borohydride MeCN-acetonitrile LDA-lithium diisopropylamidePE-petroleum ether Et₃N-triethylamine THF-tetrahydrofuran DMAP-4-(dimethylamino)pyridine AcOH-acetic acid DIPEA -N,N-diisopropylethylamine HCl-hydrochloric acid NH4OH - ammoniumhydroxide H₂SO₄-sulfuric acid EDCI- NH₄Cl-ammonium chloride1-ethyl-3-(3-dimethylaminopropyl) KOH-potassium hydroxide carbodiimideNaOH-sodium hydroxide HOBt-1-hydroxybenzotriazole K₂CO₃-potassium HATU-carbonate O-(7-azabenzotriazol-1-yl)- Na₂CO₃-sodium carbonateN,N,N′N′-tetra-methyluronium TFA-trifluoroacetic acid BINAP-Na₂SO₄-sodium sulfate 2,2'-bis(diphenylphosphanyl)- NaBH₄-sodiumborohydride 1,1'-binaphthyl

Reagents that may be used herein are purchased from commercial sourcesand can be used without further purification. Nuclear magnetic resonance(NMR) spectra are obtained on a Brucker AMX-400 NMR (Brucker,Switzerland). Chemical shifts were reported in parts per million (ppm,δ) downfield from tetramethylsilane. Mass spectra are run withelectrospray ionization (ESI) from a Waters LCT TOF Mass Spectrometer(Waters, USA).

For exemplary compounds disclosed in this section, the specification ofa stereoisomer (e.g., an (R) or (S) stereoisomer) indicates apreparation of that compound such that the compound is enriched at thespecified stereocenter by at least about 90%, 95%, 96%, 97%, 98%, or99%. The chemical name of each of the exemplary compound described belowis generated by ChemDraw software. Compounds of Formula I may beprepared by methods known in the art, for example, by followinganalogous procedures described in the International Patent ApplicationPCT/CN2013/000009 and U.S. patent application Ser. No. 13/735,467.

Example 1 Preparation of Intermediates for Preparing Compounds ofFormula I Wherein A is Phenyl

Preparation of 2,4-dichloro-6-phenyl-1,3,5-triazine

To a solution of 2,4,6-trichloro-[1,3,5]triazine (120 g, 0.652 mol) inanhydrous THF (1200 mL) was added phenylmagnesium bromide (217 mL, 0.651mol, 3 M in ether) dropwise at −10 to −0° C. under N₂ protection. Afterthe addition, the mixture was warmed to room temperature and stirred for2 hrs. The reaction was cooled to 0° C. and quenched by addition ofsaturated NH₄Cl (200 mL), then extracted with ethyl acetate. The organiclayer was dried, concentrated and purified via column chromatography(eluted with petroleum ether) to afford2,4-dichloro-6-phenyl-1,3,5-triazine as a white solid. ¹H NMR (CDCl₃) δ7.51-7.55 (m, 2H), 7.64-7.67 (m, 1H), 8.49-8.63 (m, 2H).

Example 2 Preparation of Intermediates for Preparing Compounds ofFormula I Wherein Ring A is Substituted Pyridin-2-Yl

Step 1: Preparation of 6-chloro-pyridine-2-carboxylic acid methyl ester(2-11)

To a solution of 6-chloro-pyridine-2-carboxylic acid (48 g, 0.31 mol) inmethanol (770 ml) was added concentrated HCl (6 ml). The mixture wasstirred at 80° C. for 48 hours then concentrated to remove the volatile.The crude product was diluted with ethyl acetated and washed with Sat.NaHCO₃ solution. The organic layer was dried with anhydrous Na₂SO₄ andconcentrated to give 6-chloro-pyridine-2-carboxylic acid methyl ester asa white solid.

LC-MS: m/z 172.0 (M+H)⁺.

The procedure set forth in Step 1 was used to produce the followingintermediates (2-II) using the appropriate starting material 2-I.

6-trifluoromethyl-pyridine-2-carboxylic acid methyl ester

LC-MS: m/z 206 (M+H)⁺.

Step 2: Preparation of 6-(6-chloropyridin-2-yl)-1,3,5-triazine-2,4-dione

To a solution of Na (32 g, 0.16 mol) in ethanol (500 mL) was addedmethyl 6-chloropicolinate (32 g, 0.16 mol) and biuret (5.3 g, 0.052mol). The mixture was heated to reflux for 1 hour. Then concentrated togive residue which was poured to water and added Sat.NaHCO₃ solution toadjust pH to 7, the precipitated solid was collected by filtration anddried to give 6-(6-chloropyridin-2-yl)-1,3,5-triazine-2,4-dione.

LC-MS: m/z 225 (M+H)⁺.

Step 2 was used to produce the following intermediates (2-III) startingwith appropriate intermediate 2-II.

6-(6-trifluoromethyl-pyridin-2-yl)-1H-1,3,5-triazine-2,4-dione as a palewhite solid.

LC-MS: m/z 259 (M+H)⁺.

6-pyridin-2-yl-1H-1,3,5-triazine-2,4-dione

¹H NMR (DMSO-d4): δ 11.9-12.5 (s, 1H), 11.3-11.6 (s, 1H), 8.7-8.9 (m,1H), 8.2-8.4 (m, 1H), 8.0-8.2 (m, 1H), 7.6-7.8 (m, 1H).

Step 3: Preparation of2,4-dichloro-6-(6-chloropyridin-2-yl)-1,3,5-triazine

To a solution of 6-(pyridin-2-yl)-1,3,5-triazine-2,4(1H,3H)-dione (3.0g, 013 mol) in POCl₃ (48 mL) was added PCl₅ (23 g, 0.1 mol). The mixturewas stirred at 100° C. for 2 hours then concentrated to remove thevolatile. The residue was diluted with ethyl acetated and washed withSat.NaHCO₃ solution. The organic layer was dried over anhydrous Na₂SO₄and concentrated to give2,4-dichloro-6-(6-chloropyridin-2-yl)-1,3,5-triazine as a brown solid.

LC-MS: m/z 260.9 (M+H)⁺.

The procedure set forth in Step 3 together with the appropriate startingintermediate 2-III was used to produce the following intermediates(2-IV).

2, 4-dichloro-6-(6-trifluoromethyl-pyridin-2-yl)-1,3,5-triazine as lightyellow solid.

LC-MS: m/z 294.9 (M+H)⁺.

2,4-Dichloro-6-pyridin-2-yl-[1,3,5]triazine (1.0 g, 80%) as brown solid.

LC-MS: m/z 227.0 (M+H)⁺.

Example 3 Preparation of Compounds of Formula I Wherein Ring A isSubstituted Aryl or Heteroaryl

Preparation of4-chloro-6-(4-trifluoromethyl-pyrimidin-2-yl)-[1,3,5]triazin-2-yl]-(2-trifluoromethyl-pyridin-4-yl)-amine

To a solution of2,4-dichloro-6-(4-(trifluoromethyl)pyrimidin-2-yl)-1,3,5-triazine (981mg, 3.31 mmol) in THF (80 mL) was added2-(trifluoromethyl)pyridin-4-amine (590 mg, 3.64 mmol) and NaHCO₃ (556mg, 6.6 mmol). The mixture was stirred at refluxing for 18 hours. Themixture was concentrated and poured to water, extracted with ethylacetate, dried over sodium sulphate, filtered and concentrated to give aresidue, which was purified by SiO₂ chromatography to give4-chloro-6-(4-trifluoromethyl-pyrimidin-2-yl)-[1,3,5]triazin-2-yl]-(2-trifluoromethyl-pyridin-4-yl)-amine.

LCMS: m/z 422.2 (M+H)⁺

The following intermediate was similarly prepared accordingly:

4-chloro-6-(6-(trifluoromethyl)pyridin-2-yl)-N-(2-(trifluoromethyl)pyridin-4-yl)-1,3,5-triazin-2-amine

LCMS: m/z 421.2 (M+H)⁺

4-chloro-6-(6-(1,1-difluoroethyl)pyridin-2-yl)-N-(2-(trifluoromethyl)pyridin-4-yl)-1,3,5-triazin-2-amine

LCMS: m/z 416.3 (M+H)⁺

Example 4 Preparation of6-(6-(trifluoromethyl)pyridin-2-yl)-N2-(2-(trifluoromethyl)pyridin-4-yl)-1,3,5-triazine-2,4-diamine(Compound 378)

To NH₃ in THF (10%, 15 ml) was added4-chloro-6-(6-(trifluoromethyl)pyridin-2-yl)-N-(2-(trifluoromethyl)pyridin-4-yl)-1,3,5-triazin-2-amine(2.0 g, 4.76 mmol), a precipitate was formed at the same time. Afterstirring for another 2 h, the solid was filtered and dried to give thedesired product 1.6 g (yield: 82%). MW (402.2, M+1). ¹H NMR (400 MHz,MeOH-d) δ: 8.71 (d, J=7.8 Hz, 1H), 8.52 (d, J=5.1 Hz, 1H), 8.38 (br. s.,1H), 8.24 (t, J=7.5 Hz, 1H), 8.18 (br. s., 1H), 8.01 (d, J=7.8 Hz, 1H).

Example A Enzymatic and Cell Assays

Enzymatic Assay. Compounds are assayed for IDH2 R172K inhibitoryactivity through a cofactor depletion assay. Compounds are preincubatedwith enzyme, then the reaction is started by the addition of NADPH andα-KG, and allowed to proceed for 60 minutes under conditions previouslydemonstrated to be linear with respect for time for consumption of bothcofactor and substrate. The reaction is terminated by the addition of asecond enzyme, diaphorase, and a corresponding substrate, resazurin.Diaphorase reduces resazurin to the highly fluorescent resorufin withthe concomitant oxidation of NADPH to NADP, both halting the IDH2reaction by depleting the available cofactor pool and facilitatingquantitation of the amount of cofactor remaining after a specific timeperiod through quantitative production of an easily detectedfluorophore.

Specifically, into each of 12 wells of a 384-well plate, 1 μl of 100×compound dilution series is placed, followed by the addition of 40 μl ofbuffer (50 mM potassium phosphate (K₂HPO₄), pH 7.5; 150 mM NaCl; 10 mMMgCl₂, 10% glycerol, 0.05% bovine serum albumin, 2 mMbeta-mercaptoethanol) containing 1.25 μg/ml IDH2 R172K. The testcompound is then incubated for one hour at room temperature with theenzyme; before starting the IDH2 reaction with the addition of 10 μl ofsubstrate mix containing 50 μM NADPH and 6.3 mM α-KG in the bufferdescribed above. After a further one hour of incubation at roomtemperature, the reaction is halted and the remaining NADPH measuredthrough conversion of resazurin to resorufin by the addition of 25 μlStop Mix (36 μg/ml diaphorase enzyme and 60 μM resazurin; in buffer).After one minute of incubation the plate is read on a plate reader atEx544/Em590.

For determination of the inhibitory potency of compounds against IDH2R140Q in an assay format similar to the above, a similar procedure isperformed, except that the final testing concentration is 0.25 μg/mlIDH2 R140Q protein, 4 μM NADPH and 1.6 mM α-KG, and the preincubationtime is one hour or sixteen hours.

For determination of the inhibitory potency of compounds against IDH2R140Q in a high throughput screening format, a similar procedure isperformed, except that 0.25 μg/ml IDH2 R140Q protein was utilized in thepreincubation step, and the reaction is started with the addition of 4μM NADPH and 8 μM α-KG.

U87MG pLVX-IDH2 R140Q-neo Cell Based Assay.

U87MG pLVX-IDH2 R140Q-neo cells are grown in T125 flasks in DMEMcontaining 10% FBS, 1× penicillin/streptomycin and 500 μg/mL G418. Theyare harvested by trypsin and seeded into 96 well white bottom plates ata density of 5000 cell/well in 100 μl/well in DMEM with 10% FBS. Nocells are plated in columns 1 and 12. Cells are incubated overnight at37° C. in 5% CO₂. The next day compounds are made up at 2× concentrationand 100 ul are added to each cell well. The final concentration of DMSOis 0.2% and the DMSO control wells are plated in row G. The plates arethen placed in the incubator for 48 hours. At 48 hours, 100 ul of mediais removed from each well and analyzed by LC-MS for 2-HG concentrations.The cell plate is placed back in the incubator for another 24 hours. At72 hours post compound addition, 10 mL/plate of Promega Cell Titer Gloreagent is thawed and mixed. The cell plate is removed from theincubator and allowed to equilibrate to room temperature. Then 100 ul ofreagent is added to each well of media. The cell plate is then placed onan orbital shaker for 10 minutes and then allowed to sit at roomtemperature for 20 minutes. The plate is then read for luminescence withan integration time of 500 ms to determine compound effects on growthinhibition.

Representative compound 378 was tested in R140Q enzymatic assay (16hours preincubation time) and R140Q cell-based assay as described aboveor similar thereto, having an IC50 less than 50 nM in both assays.

Having thus described several aspects of several embodiments, it is tobe appreciated various alterations, modifications, and improvements willreadily occur to those skilled in the art. Such alterations,modifications, and improvements are intended to be part of thisdisclosure, and are intended to be within the spirit and scope of theinvention. Accordingly, the foregoing description and drawings are byway of example only.

1. A compound having Formula I or a pharmaceutically acceptable salt orhydrate thereof:

wherein: ring A is an optionally substituted 5-6 member monocyclic arylor monocyclic heteroaryl; and ring B is an optionally substituted 5-6member monocyclic aryl or monocyclic heteroaryl; wherein: a. ring A andring B are not both an optionally substituted 6 member monocyclic aryl;b. when ring A is unsubstituted pyridyl, then ring B is not phenyloptionally substituted with one to three groups independently selectedfrom methyl, ethyl, t-butyl, methoxy, CH(OH)CH₃, Cl, Br, SH, and CF₃; c.when ring A is a 5-membered heteroaryl, then ring B is not phenyloptionally substituted with one to two groups independently selectedfrom F, Cl, SO₂CH₃, C(O)OCH₃, methyl, ethyl, t-butyl, methoxy, ethoxy,O-phenyl, CF₃, OH, and NO₂; d. when ring A is a 2,4-di-substituted5-thiazolyl, then ring B is not substituted phenyl; e. the compound isnot: (1) N²-2-pyridinyl-6-(3-pyridinyl)-1,3,5-triazine-2,4-diamine; (2)6-(6-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;(3)6-(2-methoxy-3-pyridinyl)-N²-(4-methylphenyl)-1,3,5-triazine-2,4-diamine;(4)N²-(3-chlorophenyl)-6-(2-chloro-4-pyridinyl)-1,3,5-triazine-2,4-diamine;(5)3-[[4-[4-amino-6-[(3-chlorophenyl)amino]-1,3,5-triazin-2-yl]-2-pyridinyl]amino]-1-propanol;(6)N-[3-[[4-amino-6-(2-methyl-4-pyrimidinyl)-1,3,5-triazin-2-yl]amino]-4-methylphenyl]-N′-[4-chloro-3-(trifluoromethyl)phenyl]-urea;(7) N⁴,N^(4′)-diphenyl-[2,2′-bi-1,3,5-triazine]-4,4′,6,6′-tetramine; (8)6,6′-(2,6-pyridinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine; or (9)6,6′-(2,3-pyrazinediyl)bis[N-phenyl-1,3,5-triazine-2,4-diamine.
 2. Thecompound of claim 1, wherein ring A is selected from phenyl, pyrazolyl,oxazolyl, isoxazolyl, pyridinyl, pyrimidinyl, pyrazinyl, and thiazolyl,wherein ring A is optionally substituted with up to two substituentsindependently selected from halo, —C₁-C₄ alkyl, —C₁-C₄ haloalkyl, —C₁-C₄hydroxyalkyl, —NH—S(O)₂—(C₁-C₄ alkyl), —S(O)₂NH(C₁-C₄ alkyl), —CN,—S(O)₂—(C₁-C₄ alkyl), C₁-C₄ alkoxy, —NH(C₁-C₄ alkyl), —OH, —CN, and—NH₂.
 3. The compound of claim 1, wherein ring B is selected fromphenyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, pyridinyl,pyrimidinyl, pyridazinyl, and pyrazinyl, wherein ring B is optionallysubstituted with up to two substituents independently selected fromhalo, —C₁-C₄ alkyl, —C₂-C₄ alkynyl, —C₁-C₄ haloalkyl, —C₁-C₄hydroxyalkyl, C₃-C₆ cycloalkyl, —(C₀-C₂ alkylene)-O—C₁-C₄ alkyl,—O—(C₁-C₄ alkylene)-C₃-C₆ cycloalkyl, —NH—S(O)₂—(C₁-C₄ alkyl),—S(O)₂NH(C₁-C₄ alkyl), —S(O)₂—NH—(C₃-C₆ cycloalkyl), —S(O)₂-(saturatedheterocyclyl), —CN, —S(O)₂—(C₁-C₄ alkyl), —NH(C₁-C₄ alkyl), —N(C₁-C₄alkyl)₂, —OH, C(O)—O—(C₁-C₄ alkyl), saturated heterocyclyl, and —NH₂. 4.A compound having Structural Formula II:

or a pharmaceutically acceptable salt thereof, wherein: ring A′ isselected from phenyl and pyridin-2-yl, wherein ring A′ is optionallysubstituted with one or two substituents independently selected fromchloro, fluoro, —CF₃, —CHF₂, —CH₃, —CH₂CH₃, —CF₂CH₃, —OH, —OCH₃,—OCH₂CH₃, —NH₂, —NH(CH₃), and —N(CH₃)₂; ring B′ is selected frompyridin-3-yl, pyridin-4-yl, isoxazoly-4-yl, isoxazol-3-yl, thiazol-5-yl,pyrimidin-5-yl and pyrazol-4-yl, wherein ring B′ is optionallysubstituted with one to two substituents independently selected fromhalo; —CN; —OH; C₁-C₄ alkyl optionally substituted with halo, CN or —OH;—S(O)₂—C₁-C₄ alkyl; —S(O)—C₁-C₄ alkyl; —S(O)₂—NH—C₁-C₄ alkyl;—S(O)₂—N(C₁-C₄ alkyl)₂; —S(O)₂-azetidin-1-yl; —O—C₁-C₄ alkyl;—CH₂—O—CH₃, morpholin-4-yl, cyclopropyl, —S(O)₂—NH-cyclopropyl;—C(O)—O—CH₃; and —C(R^(1a))(R^(2a))(R^(3a)) is selected from C₁-C₆ alkyloptionally substituted with halo or —OH; —(C₀-C₁ alkylene)-cycloalkyl,wherein the alkylene is optionally substituted with methyl and thecycloalkyl is optionally substituted with halo, —OCH₃ or methyl;saturated heterocyclyl optionally substituted with halo or methyl;—C(O)—O—C₁-C₆ alkyl; —C(O)—(C₀-C₁ alkylene)-cyclopropyl; andC(O)-benzyl.
 5. The compound of claim 4, wherein ring A′ is selectedfrom 2-chlorophenyl, 2-fluorophenyl, 2-methoxyphenyl, 3-hydroxyphenyl,6-aminopyridin-2-yl, 6-chloropyridin-2-yl,6-trifluoromethylpyridin-2-yl, and phenyl.
 6. The compound of claim 4,wherein ring B′ is selected from 2-(morpholin-4-yl)pyridin-4-yl,2-dimethylaminopyridin-4-yl, 3-(2-methyoxyethyl)phenyl,3,5-difluorophenyl, 3-chlorophenyl, 3-cyanomethylphenyl, 3-cyanophenyl,3-cyclopropylaminosulfonylphenyl, 3-dimethylaminosulfonylphenyl,3-ethylsulfonylphenyl, 3-fluorophenyl, 3-methylsulfonylphenyl,4-fluorophenyl, 5-chloropyridin-3-yl, 5-cyanopyridin-3-yl,5-cyanopyridin-3-yl, 5-cyanopyridin-4-yl, 5-fluoropyridin-3-yl,5-trifluoromethypyridin-3-yl, 6-chloropyridin-4-yl, 6-cyanopyridin-4-yl,6-cyclopropylpyridin-4-yl, 6-ethoxypyridin-4-yl, 6-fluoropyridin-3-yl,6-fluoropyridin-4-yl, 6-methylpyridin-4-yl,6-trifluoromethylpyridin-4-yl, isoxazol-4-yl, phenyl, pyridin-4-yl, andthiazol-5-yl.
 7. A pharmaceutical composition comprising a compound ofclaim 1, and a pharmaceutically acceptable carrier.
 8. The compositionof claim 7, further comprising a second therapeutic agent useful in thetreatment of cancer.
 9. A method of treating a cancer characterized bythe presence of an IDH2 mutation, wherein the IDH2 mutation results in anew ability of the enzyme to catalyze the NAPH-dependent reduction ofα-ketoglutarate to R(−)-2-hydroxyglutarate in a patient, comprising thestep of administering to the patient in need thereof a composition ofclaim
 7. 10. The method of claim 9, wherein the IDH2 mutation is an IDH2R140Q or R172K mutation.
 11. The method of claim 10, wherein the IDH2mutation is an IDH2 R140Q mutation.
 12. The method of claim 9, whereinthe cancer is selected from glioblastoma (or glioma), myelodysplasticsyndrome (MDS), myeloproliferative neoplasm (MPN), acute myelogenousleukemia (AML), sarcoma, melanoma, non-small cell lung cancer,chondrosarcoma, cholangiocarcinomas or angioimmunoblastic non-Hodgkin'slymphoma (NHL).
 13. The method of claim 9, further comprisingadministering to the patient in need thereof a second therapeutic agentuseful in the treatment of cancer.
 14. A composition of claim 7 for usein treating a cancer characterized by the presence of an IDH2 mutation,wherein the IDH2 mutation results in a new ability of the enzyme tocatalyze the NAPH-dependent reduction of α-ketoglutarate toR(−)-2-hydroxyglutarate in a patient.
 15. The composition for use ofclaim 14, wherein the IDH2 mutation is an IDH2 R140Q or R172K mutation.16. The composition for use of claim 15, wherein the IDH2 mutation is anIDH2 R140Q mutation.
 17. The composition for use of claim 14, whereinthe cancer is selected from glioblastoma (or glioma), myelodysplasticsyndrome (MDS), myeloproliferative neoplasm (MPN), acute myelogenousleukemia (AML), sarcoma, melanoma, non-small cell lung cancer,chondrosarcoma, cholangiocarcinomas or angioimmunoblastic non-Hodgkin'slymphoma (NHL).
 18. The composition for use of claim 14, furthercomprising a second therapeutic agent useful in the treatment of cancer.